BRPI0808158A2 - VEHICLE FUEL TANK ARRANGEMENT - Google Patents

Description

"VEHICLE FUEL TANK ARRANGEMENT" The present invention relates to a fuel tank arrangement for a vehicle, in particular a heavy-duty vehicle, which comprises at least one fuel tank and a fuel line assembly. wherein the fuel line assembly includes at least one fuel supply line for receiving fuel stored in the fuel tank and a fuel return line for returning excess fuel from a combustion engine to the fuel tank arrangement. .

Such fuel tank arrangements are already known in the art. In certain truck configurations, there are often two fuel tanks on the chassis, ie one on each side, to increase fuel capacity. This is particularly the case for trucks that work for long range transport. One of these fuel tanks is adapted to be a main tank that has a pickup unit to remove fuel from this tank and fuel a combustion engine. The second tank is usually presented only as another fuel storage capacity. It is connected to the main tank via a supply line, which is usually equipped with a motor-driven pump that takes fuel from the second tank and transfers it to the main tank.

Prior art DE 36 12 194 C1 describes a fuel tank arrangement having a catchment compartment in which excess returned fuel is used to draw fuel from a main compartment and feed it into a transfer line. to provide it to the pickup compartment. Return fuel flow is utilized by means of a spray pump disposed within the main tank compartment. This can lead to insufficient suction effect to supply fuel from the main tank compartment to the intake compartment.

US 6 273 131 B1 shows a similar arrangement having a relatively complicated structure at the bottom of a fuel tank.

EP 0 717 197 A2 describes a particular spray pump for use in vehicle fuel tank arrangements.

WO 91/17355 describes a fuel system in which, instead of an excessive return fuel flow received from the combustion engine, a portion of the supply fuel flow supplied via a tank-to-engine thrust pump The combustion valve returns and is used to pump fuel from a main tank compartment into a catchment compartment. This leads to a loss of pump power and requires the use of a more powerful pump to obtain a sufficient supply of fuel for the combustion engine. It is an object of the present invention to provide a fuel tank arrangement as described in the introductory part in which fuel transfer via the supply line is simplified.

This object is solved by a vehicle fuel tank arrangement, in particular heavy duty vehicles, comprising at least one fuel tank and a fuel supply line assembly for receiving the fuel stored in the fuel tank and one line. fuel return to return excess fuel from a combustion engine to the fuel tank arrangement. In accordance with the invention, the fuel supply line and the fuel return line are connected by a connecting device including a nozzle, so that the fuel flow within the fuel return line is used to take off the fuel. fuel stored in the fuel tank through the fuel supply line.

Instead of providing an additional motor driven pump for transferring fuel through the supply line, the invention provides for the use of fuel flow resulting from excess fuel returned from the combustion engine back to the fuel tank to generate an effect. pump, which is used to take fuel through the supply line and insert it into the main fuel tank. Therefore, an additional motor driven pump may be omitted and the overall arrangement may be simplified by the use of a compact coupling device including the pump.

According to one embodiment of the invention, the nozzle is formed by a Lavai nozzle or a Venturi nozzle. Such nozzle types have a simple structure and are easily obtainable. The pumping effect generated by such nozzles is sufficient to draw fuel through the supply line as discussed above. Generally, each nozzle having a low pressure side that can be used to take a fluid medium and introduce it into the present flow can be used to implement the invention. Specifically, the supply is discharged into the nozzle on its low pressure side.

The solution according to the invention is in particular applicable to a fuel tank arrangement including two fuel tanks connected to each other via the fuel supply line, wherein the connector including the nozzle is arranged between the two fuel tanks within the supply line. In particular, with regard to this embodiment, it is provided that a first fuel tank is formed as a main tank including a fuel capture unit to capture the fuel to be pumped into the combustion engine, and that a second fuel tank is formed as a secondary (passive) tank that is connected to the main tank via the supply line. In this embodiment, the first fuel tank, also called the main or active tank, is the fuel tank that is connected to the combustion engine by means of a fuel pump. The second fuel tank, which is also called the secondary or passive tank, is merely installed to increase fuel storage capacity. By using the connector with a corresponding nozzle according to the invention, fuel stored within the secondary (passive) fuel tank can be withdrawn by using the return fuel flow from the secondary tank and introduced into the main tank. . Thus, it can be ensured with little technical effort, in particular without the need for an additional motor driven pump, to obtain a sufficient amount of fuel within the main tank. In other words, situations in which the main tank is nearly empty can be avoided, while the secondary (passive) tank is substantially full of fuel.

According to an alternative embodiment of the invention, the fuel tank includes a main tank compartment and a catchment compartment, wherein the main compartment is connected to the capture compartment by means of a transfer line. According to this embodiment, the main tank compartment may be separated from the intake compartment by a partition wall, wherein the partition wall provides an overflow of the intake compartment in the main tank compartment.

According to one aspect of this embodiment, the transfer line extends over the partition wall and carries fuel from the main tank compartment into the intake compartment, wherein the connector is disposed within the main tank compartment.

Alternatively, the supply line moves out of the fuel tank, where the connector is disposed outside the fuel tank, and where the transfer line moves into the intake compartment to carry fuel from the fuel tank. connection into the pickup compartment.

According to another alternative to this embodiment, the supply line travels through the partition wall and carries fuel from the main tank compartment into the intake compartment, wherein the connector is disposed within the intake compartment.

In all these embodiments, the fuel return line always leads to the connector.

Furthermore, according to another aspect of the invention, the supply line or transfer line may be provided with a check valve to prevent a counterflow of fuel through the supply line or transfer line.

In the following embodiments of the invention, a detailed description is given with reference to the figures, in which:

Figure 1 is a schematic view of a fuel tank arrangement according to the invention.

Figure 2 is a schematic view of a possible nozzle drawing,

Figure 3 shows another embodiment of a fuel tank arrangement according to the invention,

Figure 4 shows another embodiment of a fuel tank arrangement according to the invention, and

Figure 5 shows another embodiment of the fuel tank arrangement according to the invention.

In Figure 1, a fuel tank arrangement 10 is shown in a schematic drawing. The fuel tank arrangement 10 comprises a main tank 12 and a secondary (passive) tank 14. The two tanks 12, 14 are arranged on two opposite sides of a vehicle chassis, such as a heavy duty vehicle.

The main tank 12 is connected via a suction line 16 to a combustion engine (not shown) which includes a fuel pump for taking fuel from the fuel tank 12. The secondary (passive) fuel tank 14 is connected with the main fuel tank by means of a fuel supply line 18 and a transfer line 19. The fuel supply line 18 dips into the fuel contained in the secondary tank 14 and the fuel transfer line 19 dips into the fuel contained in the main tank 12 through its free ends 20 and 22 respectively. Between the fuel supply line 18 and the transfer line a connector 24 is arranged. The connector 24 is also fluidly connected to a fuel return line 26 which carries excess fuel from the combustion engine. returns to fuel tank arrangement 10. Within fuel return line 26, fuel flows in a more or less regular flow 40 during combustion engine operation.

The connector 24 includes a mouthpiece 28 as shown in Figure 2 in a schematic drawing. The nozzle 28 has a housing 30 that forms a passageway 32 therethrough. The passageway 32 includes a conical part 36 and an extending part 38 forming a Laval or Venturi nozzle. A discharge opening 40 opens into the extending portion 38.

During run time, the continuous excess fuel flow 40 returned from the combustion engine flows into the connector 24. It enters the tapered part 36 as shown in Figure 2. As it flows through the tapered part 36, the pressure increases (high pressure side 48). As it enters the extending part 38, the pressure decreases again, whereby a vacuum is generated (low pressure side 50). This vacuum is used to draw fuel through the discharge port 41 of the fuel tank 14 and the supply line 18 and to introduce it into the extending part 38. Thus, a combined fuel flow 44 composed of the excess fuel 40 returned from the fuel engine as well as fuel 42 withdrawn from the secondary tank flows into main tank 12 via transfer line 19. From main tank 12, a fuel flow 46 is conducted to the engine fuel pump of combustion.

Thus, according to the invention it can be ensured that with little technical effort the fuel stored in the secondary tank 14 is permanently introduced into the main tank 12 using the fuel flow 40 resulting from the fuel returned from the combustion engine.

This principle according to the invention may also be used in embodiments having a fuel tank arrangement 110 with a main tank and a catchment tank compartment. Figure 3 shows such an embodiment. The fuel tank arrangement 110 according to Figure 3 includes a main tank compartment 112 and a intake tank compartment 114. The main tank compartment 112 and the intake tank compartment 114 are separated from each other by means of of a partition wall 160. Excess fuel is returned from the combustion engine via a fuel return line 126. The fuel return line runs into the fuel tank arrangement 110 and is connected with a device 124 at the bottom of the main tank compartment 112. A transfer line 119 runs from the connector 124 upwards and extends over the upper edge of the partition wall 160, which forms an overflow between the bulk tank compartment 114 and main tank compartment 112. Transfer line 119 carries fuel from connector 124 into intake tank compartment 114. From the bottom of the intake tank compartment 114, a suction line 116 leads to a suction pump associated with the combustion engine.

Figure 3 shows two different fuel levels 162 and 164. Fuel level 162 represents the fuel level within the main tank compartment.

112, while fuel level 164 represents the fill state within the intake tank compartment 114. As long as there is sufficient fuel within the fuel tank arrangement 110, the fuel level within the intake tank compartment 114 it should be close to the upper edge of the partition wall 160 to ensure a permanent fuel supply to the combustion engine via suction line 116.

Figure 3 also shows the fuel flows: The return fuel 140 flowing from the combustion engine into the main tank compartment 112 is supplied to the connector 124. In it, through the supply line not shown, The fuel is drawn from the main tank compartment 112 and a combined fuel stream 144 is supplied to the intake tank compartment 114 via transfer line 119. This leads to a condition in which the intake tank compartment 114 is constantly in operation. a fill condition similar to the similar condition shown in Figure 3, that is, in a fill condition that has a fuel level 164 near the upper edge of the partition wall 160. Fuel is drawn from the intake compartment 114 through the suction line 116 as shown with fuel flow 146.

Figure 4 shows another similar embodiment. The difference between the modalities 15 according to Figures 3 and 4 is the arrangement of the connector 124. According to Figure 4, the connector 124 is disposed outside the main tank compartment 112 on the outside of the arrangement. Thus, supply line 118 leads to connector 124. In addition, return line 126 leads to connector 124. Transfer line 119 also partially runs 20 out of the tank. and enters the fuel tank above the intake tank arrangement 114. It then runs down to the bottom of the intake tank compartment 114. As already shown in Figure 3, the suction line is arranged parallel to this vertical part of the transfer line 119.

The function is the same as that described with reference to Figure 3. The fuel is pumped out of main tank compartment 112 via supply line 118 according to fuel flow 142. Return fuel flow 140 within the return line 126 is used to generate a pumping effect within the connector 124. A combined fuel flow 144 then flows through the transfer line 119 into the intake compartment 114 so as to 30 maintain fuel level 164 for as long as possible near the upper edge of partition wall 160.

Figure 5 shows another embodiment of the invention, in which the connector 124 is disposed within the intake compartment 114. The supply line 118 leads through the lower part of the partition wall 160 of the main tank compartment 112 to inside the intake tank compartment 114 to bring a fuel flow 142 to the connector 124. The return line 126 runs from the combustion engine into the fuel tank arrangement 110 down to the connector 124 to guide the return fuel flow 140. The transfer line 119 is very short and also arranged at the bottom of the intake compartment region 114. The suction line 116 is arranged as already described with reference to Figures 3 and 4.

5 Again, the function is the same as described above. The fuel is taken from the

main tank compartment 114 via supply line 118 through partition wall 160 as indicated by fuel flow 142. Connector 124 utilizes return fuel flow 140 to generate a pumping effect, whereby a Combined fuel 114 is brought into the intake compartment 114 via transfer line 110. Thus, fuel level 164 in intake compartment 114 can be maintained at a high level, in particular near the upper edge of the wall. partition 160.

In embodiments according to Figures 3 to 5, the supply line 118 or transfer line 119 may be provided with non-return valves (not shown) to prevent undesirable counterflow of fuel from the intake compartment into the main tank compartment.

Claims (5)

1. Vehicle fuel tank arrangement (10; 110), in particular in heavy duty vehicles, comprising a fuel tank (12, 14; 112, 114) including a main tank compartment (112) and a intake compartment (114) and a fuel line assembly, wherein the fuel line assembly includes at least one fuel supply line (18; 118) for receiving the fuel stored in the main tank compartment (112), and a fuel return line (26; 126) for taking up excess fuel from a combustion engine at the fuel tank arrangement (10; 110), whereby the fuel supply line (18; 118) and the fuel return line (26; 126) are connected by a connector (24; 124) including a nozzle (28) such that the fuel flow (40; 140) within the fuel return line ( 26; 126) is used to remove the arm fuel in the main tank compartment (112) via the fuel supply line (18; 118), characterized by the fact that the Lifting device (24; 124) is disposed outside the fuel tank and connected to the intake compartment (114) by means of a transfer line (119) to carry fuel from the connecting device. (124) into the pickup compartment (114). Fuel tank arrangement (10; 110) according to claim 1, characterized in that the supply line (18; 118) discharges into the nozzle (28) at its low pressure side. (50). Fuel tank arrangement (10) according to claim 2, characterized in that the nozzle (28) is formed by a Laval nozzle or a Venturi nozzle. Fuel tank arrangement (110) according to claim 6, characterized in that the main tank compartment (112) is separated from the intake compartment (114) by a partition wall (160) in that the partition wall (160) provides an overflow from the intake compartment (114) into the main tank compartment (112). Fuel tank arrangement (10; 110) according to one of the preceding claims, characterized in that the supply line (18; 118) is provided with a check valve.